Data/Floating.hs

   1 {-
   2  - Copyright (C) 2009-2010 Nick Bowler.
   3  -
   4  - License BSD2:  2-clause BSD license.  See LICENSE for full terms.
   5  - This is free software: you are free to change and redistribute it.
   6  - There is NO WARRANTY, to the extent permitted by law.
   7  -}
   8
   9 -- | Top level module for alternative floating point support.
  10 module Data.Floating (
  11     module Data.Floating.Classes,
  12     Double, Float,
  13     module Data.Floating,
  14     toFloating
  15 ) where
  16
  17 import Prelude hiding (RealFloat(..), RealFrac(..), Double, Float)
  18 import Data.Floating.Classes
  19 import Data.Floating.Instances
  20 import Data.Floating.Types
  21 import Data.Floating.Types.Double
  22 import Data.Floating.Types.Float
  23 import Data.Floating.Environment
  24
  25 import Control.Monad
  26
  27 isInfinite :: PrimFloat a => a -> Bool
  28 isInfinite = (== FPInfinite) . classify
  29
  30 isNaN :: PrimFloat a => a -> Bool
  31 isNaN = (== FPNaN) . classify
  32
  33 isNormal :: PrimFloat a => a -> Bool
  34 isNormal = (== FPNormal) . classify
  35
  36 isSubNormal :: PrimFloat a => a -> Bool
  37 isSubNormal = (== FPSubNormal) . classify
  38
  39 isFinite :: PrimFloat a => a -> Bool
  40 isFinite = not . liftM2 (||) isInfinite isNaN
  41
  42 isNegativeZero :: PrimFloat a => a -> Bool
  43 isNegativeZero = liftM2 (&&) ((== FPZero) . classify) ((== (-1)) . signum)
  44
  45 -- | @fquotRem x y@ computes the remainder and integral quotient upon division
  46 -- of x by y.  The result is (x-n*y, n), where n is the value x/y rounded to
  47 -- the nearest integer.
  48 fquotRem :: RealFloat a => a -> a -> (a, a)
  49 fquotRem x y = (frem x y, nearbyint (x/y))